Very often I need to confirm some output - and browser caches are notoriously overzealous at not always returning the very latest version. It is of course possible to (attempt) to switch this stuff off but it seems hit and miss even these days.
One extremely handy feature that the Chrome developer tools dialog has, under the network section is the ability to copy a request as a
cURL command. It's had this since March 2013 but it seems to be secret knowledge to many.
This will load your clipboard up with a paste & go command, sessions included. This is insanely handy - you can see exactly what's coming out of the server without any fear of browser 'tweaks', have it repeatedly get called and
grep the output, all kinds of usefulness.
If you're wondering what a
HAR file is it's an HTTP Archive - a format that allows interchange of HTTP request and session data in one go. It's handy when you need to share and debug a connection over email for instance.
If you remember only one thing though, remember the right click menu on network resources within Chrome!